Today, there is increasing interest among Swedish growers in biological diversity within the agricultural landscape. Many scientific studies have highlighted the services performed by beneficial organisms, which can help to improve the quantity and quality of crops. One tremendously important ecosystem service is biological control of pest insects and mites. The question is what growers can actually do to increase the abundance and diversity of natural enemies and whether this will have an impact on the pest population and, more importantly, on yield and quality of the crop. Another question is whether biodiversity is always positive for growers or whether there are negative aspects that should be dealt with. These relevant questions are addressed in the present report, the aim of which is to enlarge the current knowledge base on how to improve conditions for natural enemies, so-called habitat manipulation, within annual vegetable crops and perennial apple cropping systems. However, our aim was not to conduct a complete review of all available literature, but instead to select studies that may be of particular value for advisors and growers.
We also chose to include the outcomes of a workshop on increasing diversity in apple orchards and interviews with advisors and vegetable growers to investigate the attitude and state of knowledge on habitat manipulation in Sweden today. We focus on natural enemies, arthropod pests and practices applied at field scale, and therefore exclude applications developed for greenhouse crops. Our hope is that advisors and interested growers in particular will find this report relevant and rewarding